Thread cutting die



O a Y B 7 E I D Sept. 15, 1936.

INVENTOR ATTONEY Patented Sept. 15, 1936 UNITED STATES PATENT OFFICE 1 Claim.

The invention relates to a screw cutting die or what is known as a threading die.

The primary object of the invention is the provision of a die or hollow mill in which the cutting edges of the thread cutting threads may be sharpened in an easy, positive and expeditious manner by a rotating wheel, having a cross sectionally V-shaped or tapered periphery moving between the jaws of the die or hollow mill.

A further object is the provision of a thread cutting die or hollow mill, in which the spaced jaws thereof are arranged an equal distance apart and have their confronting flat walls parallel and in which each jaw at the thread cutting inner surface thereof has side extensions, which from said thread cutting portions are thickened but have their side walls arranged at an inward angle of approximately and whereby a grinding wheel travelling between the jaws, and having a tapered or cross sectoinally V- shaped periphery will act up the right angular side of the cutting edge of each jaw to easily and quickly sharpen the same.

Another object of the invention is the provision of a die of this character, wherein the wall between the spaced jaws is tapered to have its sides arranged at opposite inward angles to provide a stop for the sharpening wheel and to likewise provide a guide for directing metal shavings from between the jaws of the die or hollow mill, and to also provide a die or hollow mill that will thread a pipe or the like and produce more threads in a minimum period of time than the standard types of dies.

A further object of the invention is the provision of a die of this character, which is simple in construction, thoroughly reliable and eflicient in its operation, strong, durable, readily and easily ground, and inexpensive to manufacture.

With these and other objects in View, the invention consists in the features of construction, combination and arrangement of parts as will be hereinafter more fully described, illustrated in the accompanying drawing, which discloses the preferred embodiment of the invention and pointed out in the claims hereunto appended.

In the accompanying drawing:

Figure 1 is a side elevation of the die constructed in accordance with the invention and having applied thereto a clamping ring of usual construction.

Figure 2 is an end view.

Figure 3 is a fragmentary enlarged side elevation.

Figure 4 is a sectional view on the line 4-4 of Figure 2 looking in the direction of the arrows.

Figure 5 is a sectional view on the line 5-5 of Figure 2 looking in the direction of the arrows.

Figure 6 is a sectional view on the line 66 of Figure 3 looking in the direction of the arrows.

Similar reference chracters indicate corresponding parts throughout the several views in the drawing.

Referring to the drawing in detail, A designates generally a thread cutting die or hollow mill, slotted longitudinally from its outer end to provide equidistantly spaced parallel jaws l0 which at their inner sides are provided wtih a series of pipe threading threads or teeth l I. The integral block like extending thread cutting portions of the jaws do not have their sides arranged in the same plane with that of the straight sides of said jaws, but said tooth carrying blocks or thread cutting portions 03 of the jaws have their said sides disposed from their cutting teeth H, at an inward angle of approximately 45 with respect to the said parallel straight sides of the jaws. Also the confronting edges of the block like parts l3 are slightly spaced. This permits a grinding wheel, having a cross sectionally V-shaped periphery that has at least one of its faces abrasive travelling between the adjacent jaws to act upon and sharpen the cutting edge of the cutting tooth carrying block l3 of the jaw.

Embracing the die A is the customary clamp ring I4, its clamping action being had through the medium of a screw l5. By reason of the tapered formation of the working sides of the jaws Hi there is assured a cutting action at the outer end of the jaws.

The opening I6 in the die is exactly at the center thereof and such die in use will cut a smooth thread and the same will not clot when backing out as the teeth will cut from the rear as well as from the front of the die. The inner walls provided by the slots between the jaws are tapered and each has opposite angle sides which coincide with the peripheral edge of the sharpening wheel and which also serve as a means for directing pipe shavings through the die or hollow mill.

What is claimed is:

A pipe threading implement comprising a body which is round in cross section and which has a round bore that enters from one of its ends and. which has, spaced longitudinally extending slots that enter the bore and whose confronting walls are parallel and which provide the implement with compressable jaws that are substantially tri-angular in cross section, each of said jaws, on the inner face thereof having a rectangular block-like extension which projects into the bore and which has on its outer face a plurality of cutting teeth which extend arcuately from one to the second side thereof, and the said confronting walls of the jaws extending beyond said block-like extensions and having their ends tapered from the outer surface of the body toward the bore therein.

ADOLF GOOB. 

